From Consumer Wiki

GASOLINE

Gasoline pricing is not regulated by any state or federal agency. If a consumer is unhappy with the price of gasoline, direct them to the California Energy Commission or to their elected representatives to file a complaint.

State level has responsibility for measurement standards regulations for advertising, quantity, octane number, price posting, nozzle problems, absence of air, gas pumps or gauge for measuring air pressure. See Weights and Measures (County) for all county offices and phone numbers to report problems or get information.

Gasoline sales with mandatory purchase of additional service (such as a car wash) are prohibited by California Business and Professions Code Section 20735. Complaints are handled by the local county or city District Attorney's Office for the particular county.